Conventional toilets typically have a tank and a bowl. Each of the tank and/or the bowl can be distinct features attached to each other or they can be integrally formed as one single apparatus. With respect to the tank, it has been known to be situated above the bowl in some manner and typically disposed towards the rear portion of the bowl itself. The tank is designed to store liquids that can be later used for activating a flush of the bowl in order to remove contents including liquid and solid waste deposited in the bowl.
Activation of a flush causes the contents in the bowl to be delivered to a drain line in communication with the bowl itself. To activate a flush, the user may depress a button or flush lever externally positioned on the tank causing a flush valve positioned inside the tank to release water into the bowl. With this in mind, it is important to understand what may be achieved through activation and completion of a particular flush cycle. Primarily, liquid and solid waste is removed from the bowl. Additionally, the flush cycle causes the bowl to be cleaned from the waste previously stored therein including any particulate which may have adhered or otherwise lodged to the inner portion of the bowl.
In gravity fed toilets that utilize a siphon during the flush cycle, the toilet is designed so that a syphon is typically formed in the trapway of the toilet when water is added to the bowl. More specifically, the trapway may have a U-shaped tube that draws water from the bowl to the drain line. In practice, however, flush activation may cause water in the tank to travel into the bowl and spill over the highest point in the trapway at a rate greater than the water can exit the trapway into the drain line.
At some point enough air in the trapway is removed in a manner that activates the siphon effect in the trapway thereby causing any remaining liquids in the bowl to be drawn to the drain line. Consequently, because most of the air must be removed from the portion of the trapway closer to the drain line to initiate a siphon, conventional toilets usually utilize trapways with relatively small diameters. However, reducing the diameter of the trapway can lead to clogging of waste inside the trapway.
In recent years, gravity-fed siphoned toilets have improved their capability of disposing of waste through siphon jets using rim-jet designs or direct-jet designs. In a rim-jet design approach, activation of a flush causes water to travel from the tank through an inlet of the bowl and through a manifold leading to a channel of the toilet rim. In this respect, the water from the tank may be delivered onto and/or around the bowl's perimeter through one or more apertures of the bowl under the rim. During a flush, the tank also delivers water through a jet disposed on the rim. This rim-jet is connected to the bowl and its relative opening is typically characterized to deliver water directly at the opening in the trapway. In rim-jet designs, water flows through the jet in a manner that fills the trapway of the toilet quicker than with toilets lacking the rim-jet. Because the rim-jet increases the rate of flow for the water to the trapway, the trapway is no longer limited by trapway diameter as previously discussed. This has been advantageous in overcoming the previously-referenced clogging of accumulated waste in trapways.
Direct-jet designs similarly send water from the tank to the inlet of the bowl and through the manifold. However, this water is divided by the design into a first portion directed towards the inlet of the rim to clean the bowl whereas a second portion is directed through a direct-jet that is coupled to the manifold. This direct-jet can be dimensioned in a manner to deliver water directly at the opening of the trapway at desired flow rates. Accordingly, water delivered from the direct-jet to the trapway causes the trapway to likewise be filled quickly.
Both rim-jet and direct-jet designs suffer in several notable manners. For one, because water has grown increasingly scarce, there remains a constant need in the industry to develop flush systems that increase flush efficiency that in turn consume fewer gallons per flush. In this race towards efficiency, there also exists a need to optimize respective jet and trapway design without sacrificing performance including cleanliness of the bowl or total manufacturing costs. There also exists a need to produce a flushing system that is easy to install and maintain to conserve vital labor costs. There also exists a need to resolve issues with unplanned backflow of dark water into the tank in order to both protect architecture inside the tank as well as well as to maintain low system maintenance costs. Finally, there exists a need for siphon flush systems that draw upon direct-jet and/or rim-jet designs that avoid trapway clogging while also maintaining compliance with relevant field standards and regulations.